Computer controlled balsa router

As a follow-up to yesterday’s post, [owen] sent along a link to his computer controlled router table for balsa cutting. This was his project before switching to lasers and sheetmetal. The write up starts with an interesting discussion about CNC not really being a magical tool or time saver. Sure, it can be pretty quick about cutting accurate pieces, but you still have to assemble it. Most likely all of the time you saved cutting was spent designing and prepping, which you could have spent cutting accurate parts by hand. Owen had extra time to spend designing since he was traveling for business. He does admit that the ability to quickly generate replacement parts has made him a more courageous pilot.

Yes, I did think of a network router actually, we’re a sad breed of nerds.

I would like to say though that he is correct, a CNC machine for balsa is kinda lame in that fact that it takes more time and energy to make than to just cut it by hand. Most people do not use them for balsa though, which happens to be really easy to cut… they are for metal or harder woods, plastics, etc.

not to mention, like many hacks on this site, they are to see if you can do it.

Anyone know where I can get information on cnc programming? For instance if someone has a CNC machine, what programs do I use to create my technical drawing that they can import in to most CNC machines. Is there some language or program that’s more popular then others?

Although the real nice thing, as implied in the article, is once it’s designed you can replicate the parts exactly time and time and time again. R/C plane nicks a chain-link fence breaking a couple ribs in the wing?? No problem. Have the machine make a few new ribs which are exactly like the original, cut out the bad bits, glue in the new bits, put a patch cover over the repaired section, and voila.

Gets even more interesting when one has a complex compound wing design where no three ribs are of the same shape or size. Just tell the cnc to cut out ribs #4, #5, and #7, and commence with repairs once the replacements are in hand.

As stated, the time savings isn’t in the initial design and buildup… The time savings is realized when further copies of the original parts are needed. Design once, cut many…

#5: gcode is the standard language for controling nc machines. you can write it from scratch. many drawing programs will also output gcode files that you run on your machine. The following is a pretty good intro to gcode from linuxcnc http://www.linuxcnc.org/handbook/gcode/g-code.html